Universal rotary cup type spraying equipment for inner wall of curing coating oil pipe

Abstract

The invention discloses universal rotary cup type spraying equipment for the inner wall of a curing coating oil pipe. The universal rotary cup type spraying equipment comprises a pneumatic motor, a rotary cup supporting transmission shaft and a rotary cup. According to the universal rotary cup type spraying equipment for the inner wall of the curing coating oil pipe, a rotary cup supporting transmission shaft is fixedly installed at the output end of a pneumatic motor, a rotary cup is fixedly installed at the front end of the rotary cup supporting transmission shaft, a paint cavity is formed in the rotary cup, and three vertical paint mist outlets are formed in the side wall, corresponding to the circumference of the paint cavity, of the rotary cup; a paint conveying pipe matched with the outer contour of the pneumatic motor is arranged outside the pneumatic motor, the front end of the paint conveying pipe is inserted into a paint cavity of the rotary cup, the outer side of the rotary cup is covered with a dispersion net, and the self-made pneumatic rotary cup device is adopted for coating of green novel heavy anti-corrosion paint on the inner wall of a conventional oil pipe (phi 73 * 5.51 mm). The whole gun barrel is automatically controlled to hold the pneumatic rotating cup device to move back and forth in the oil pipe, the coating process of paint on the inner wall of the oil pipe is completed, and the final formed coating film meets the industrial standard technical requirements.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of oilfield technical services (the field of oilfield tubing anticorrosion technology), and particularly relates to a general solidified coating tubing inner wall rotary cup type spraying equipment. BACKGROUND

[0002] The coating tubing product is applied to the water injection string of the water injection well, and because the water quality of the oilfield water injection is corrosive, the service in the inner wall of the oilfield water injection well string is subjected to the corrosion of the flowing medium of the inner wall. If the bare pipe is used for water injection operation, the service life is greatly shortened. For the conventional oilfield, the inner wall of the water injection string is generally protected by the organic coating protection measure, which can greatly increase the service life of the water injection string of the water injection well and reduce the oilfield exploitation cost.

[0003] According to the patent document with the publication number CN101625063B, a manufacturing method of an oil pipe nano anti-corrosion coating is disclosed, which includes an oil stain treatment step and a sand blasting treatment step. The method has the following steps: A, clean the oil stains on the oil pipe, if there are no oil stains, directly proceed to the following steps; B, sand blasting treatment: treat the inner and outer circumferential wall surfaces of the oil pipe by sand blasting, so that the sand blasting level of the inner and outer circumferential wall surfaces of the oil pipe reaches Sa2.5 or Sa2.5 or more, surface anchor degree of 10-40 microns; C, within 24 hours after completing the above step B, the sandblasted oil pipe is placed in a dry environment, and a nano composite coating is applied on the inner and outer circumferential walls of the oil pipe: ① the coating method for the inner wall of the oil pipe body - a long rod transmission spray head is used to spray a primer composed of nano coating on the inner circumferential wall surface along the axis of the oil pipe in a reverse walking manner parallel to the oil pipe axis, and the oil pipe body itself is correspondingly rotated around its oil pipe center axis to make the primer fully cover the inner circumferential wall surface; the coating method for the outer wall of the oil pipe body - a primer composed of nano coating is sprayed on the outer circumferential wall surface by starting from one end of the oil pipe outside and walking parallel to the oil pipe wall, and the oil pipe itself is correspondingly rotated to make the primer fully cover the outer circumferential wall surface, so as to form a first primer coupling layer on the inner and outer circumferential wall surfaces of the oil pipe respectively, which is attached to the exposed steel base of the sandblasted inner and outer circumferential wall surfaces of the oil pipe respectively, the thickness of the first primer coupling layer formed on the outer circumferential wall surface or the thickness of the first primer coupling layer formed on the inner circumferential wall surface is 30-50 microns, and the primer is cured at 70°C-100°C for 25-50 minutes; ② on the basis of the above step ①, a middle coating composed of nano coating is sprayed on the surface of the first primer coupling layer on the inner and outer circumferential walls of the oil pipe body respectively by using the coating method described in step ①, so as to form a second middle anti-permeation layer on the surface of the first primer coupling layer on the inner and outer circumferential walls of the oil pipe respectively, the thickness of the second middle anti-permeation layer formed on the surface of the first primer coupling layer on the outer circumferential wall or the thickness of the second middle anti-permeation layer formed on the surface of the first primer coupling layer on the inner circumferential wall is 40-60 microns, and the primer is cured at 70°C-100°C for 25-50 minutes; ③ on the basis of the above step ②, a surface coating composed of nano coating is sprayed on the surface of the second middle anti-permeation layer on the inner and outer circumferential walls of the oil pipe body respectively by using the coating method described in step ②, so as to form a third surface functional layer on the surface of the second middle anti-permeation layer on the inner and outer circumferential walls of the oil pipe respectively, the thickness of the third surface functional layer formed on the surface of the second middle anti-permeation layer on the outer circumferential wall or the thickness of the third surface functional layer formed on the surface of the second middle anti-permeation layer on the inner circumferential wall is 30-50 microns, and the primer is cross-linked and cured at 180-220°C for 1-3 hours; D, the total thickness of the three-layer nano composite coating completed in the above step C is tested, and the oil pipe is packaged and stacked after passing the test.

[0004] To provide better protection for oil pipes, the existing coating was upgraded. However, the existing general-purpose curing coating (commercially available green heavy-duty anti-corrosion coating) used after the upgrade is no longer suitable for the current oilfield oil pipe corrosion protection performance requirements due to differences in resin type, solvent system, filler composition, and additives. The coating film formed does not meet the technical requirements of the industry standard SYT6717-2016. Since the upgraded general-purpose curing coating is usually a green and environmentally friendly high-solids latent curing coating, and based on the high solids and high viscosity characteristics of high-solids latent curing coatings, the patent applicant of this invention has updated and upgraded the existing curing coating application method and equipment to meet the characteristics and requirements of the current green heavy-duty anti-corrosion coating (existing general-purpose curing coating). Summary of the Invention

[0005] The purpose of this invention is to provide a universal rotary cup spraying equipment for curing coatings on the inner wall of oil pipes, so as to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, the present invention provides the following technical solution: A general-purpose rotary cup spraying device for the inner wall of a curing coating pipe includes a pneumatic motor connected to the front end of the nozzle transmission rod. A rotary cup support drive shaft is fixedly installed at the output end of the pneumatic motor. A rotary cup is fixedly installed at the front end of the rotary cup support drive shaft. The rotary cup has a paint chamber inside. Three vertical paint mist outlets are opened on the side wall of the rotary cup corresponding to the circumference of the paint chamber. A paint delivery pipe adapted to the outer contour of the pneumatic motor is provided outside the pneumatic motor. The front end of the paint delivery pipe is inserted into the paint chamber of the rotary cup. The paint chamber is open. Multiple fixing seats are fixedly connected to the outer wall of the paint delivery pipe. The fixing seats are welded and fixed to the housing of the pneumatic motor. A paint pipe connector is fixedly connected to the tail end of the paint delivery pipe. An air pipe connector is fixedly connected to the tail end of the pneumatic motor. A dispersion net is provided on the outer cover of the rotary cup.

[0007] As a further embodiment of the present invention: the rotating cup support drive shaft includes a connecting part, a clamping part, an extension part and a threaded part, which are arranged sequentially. The connecting part has a length of 24mm and a diameter of 6mm, the clamping part has a length of 9mm and a diameter of 8mm, the extension part has a length of 37mm and a diameter of 6.85mm, and the threaded part has a length of 19.5mm and a thread size of M5.

[0008] As a further embodiment of the present invention: the connecting part is used to connect with the pneumatic motor, the threaded part is used to connect with the rotary cup, the rotary cup is threadedly connected to the threaded part, the connecting part is inserted into the chuck of the pneumatic motor, the end of the threaded part extends out of the rotary cup and is threadedly connected with a nut, and the rotary cup is provided with a rotary cup base fixing rod screw hole for threaded connection of the threaded part and through.

[0009] As a further embodiment of the present invention: the rotating cup is inverted conical trapezoid, and the dispersing net is inverted conical trapezoid adapted to the rotating cup.

[0010] As a further embodiment of the present invention: the screw hole of the base fixing rod of the rotary cup is located at the large end of the rotary cup, and the paint cavity is open to the small end of the rotary cup.

[0011] As a further embodiment of the present invention: the dispersing net is fixedly installed to the rotary cup by bolts, and the rotary cup is provided with threaded holes for bolt thread connection.

[0012] As a further embodiment of the present invention: the front end of the paint supply pipe is sealed, and two paint outlet holes are opened at 180° diagonally on the paint supply pipe. The specifications of the paint supply pipe are Ф4.0×1.0mm, the specifications of the paint outlet holes are Ф1.0mm, one of the paint outlet holes is 4.5mm away from the top of the paint supply pipe, and the other paint outlet hole is 9.5mm away from the top of the paint supply pipe.

[0013] A method for applying a general-purpose rotary cup sprayer for curing coatings to the inner wall of oil pipes, comprising the following steps: Step 1: Preparation. Disperse the existing general-purpose curing coating using a dispersion device. Connect the rotary cup spraying equipment on the inner wall of the oil pipe to the front end of the nozzle transmission rod. Connect the paint supply pipe to the paint supply machine through the paint pipe connector. Connect the pneumatic motor to the air compressor through the air pipe connector. Step Two: Spraying. High-speed rotary cup high-pressure airless spraying is driven by a pneumatic motor. The rotary cup rotates at high speed under the drive of the pneumatic motor. The paint is transported to the paint chamber of the rotary cup through the paint delivery pipe. In the high-speed rotating rotary cup, the paint adheres to the inner cup surface due to centrifugal force. Under the action of centrifugal force, it is atomized at the vertical paint mist outlet. The atomized paint is then passed through the dispersion mesh by the centrifugal force of the rotary cup and adheres to the inner wall of the oil pipe to form a continuous and uniform coating film. During the spraying process, the rotary cup spraying equipment sprays the inner wall surface of the oil pipe by moving backward along the axis parallel to the oil pipe axis.

[0014] Compared with the prior art, the beneficial effects of the present invention are: 1. This invention uses a self-made pneumatic rotary cup device to apply a new type of green heavy-duty anti-corrosion coating to the inner wall of a conventional oil pipe (Ф73×5.51mm). The automated control of the overall gun rod holding the pneumatic rotary cup device moves backward inside the oil pipe to complete the coating process on the inner wall of the oil pipe. The final coating film meets the technical requirements of industry standards.

[0015] 2. This invention features a self-designed aluminum alloy conical trapezoidal rotary cup with three vertically oriented windows at 120° angles to enhance atomization. A dispersion mesh covers the rotary cup to further promote atomization. The paint delivery pipe has two holes at 180° angles to each other, staggered and positioned in the middle of the rotary cup. This ensures a more uniform distribution of paint supply, resulting in excellent surface quality, continuous and uniform coating, and is environmentally friendly and energy-saving. It is suitable for high-solids, high-viscosity coatings, reducing solvent usage. Furthermore, this green, new type of heavy-duty anti-corrosion coating uses environmentally friendly solvents, further reducing solvent consumption. Attached Figure Description

[0016] Fig. 1 This is a schematic diagram of a general-purpose rotary cup spraying equipment for the inner wall of a curing coating oil pipe.

[0017] Fig. 2 This is a diagram illustrating the rotary cup support drive shaft in a general-purpose rotary cup spraying equipment for the inner wall of a curing coating oil pipe.

[0018] Fig. 3 This is a diagram illustrating the rotary cup in a general-purpose rotary cup spraying equipment for coating the inner wall of an oil pipe.

[0019] Fig. 4 This is a diagram showing the end of the paint delivery pipe in a general-purpose rotary cup spraying equipment for coating inner walls.

[0020] Fig. 5 This is a physical demonstration of a general-purpose rotary cup spraying equipment for coating the inner wall of oil pipes.

[0021] In the diagram: 1. Pneumatic motor; 2. Rotary cup support drive shaft; 3. Rotary cup; 4. Paint chamber; 5. Vertical paint mist outlet; 6. Paint delivery pipe; 7. Fixing base; 8. Paint pipe connector; 9. Air pipe connector; 10. Dispersion net; 11. Connecting part; 12. Clamping part; 13. Extension part; 14. Threaded part; 15. Nut; 16. Paint outlet hole; 17. Rotary cup base fixing rod screw hole. Detailed Implementation

[0022] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0023] Please see Figs. 1-5In this embodiment of the invention, a general-purpose rotary cup spraying equipment for the inner wall of a curing coating oil pipe includes a pneumatic motor 1 connected to the front end of the nozzle transmission rod. The pneumatic motor 1 is a Jubai brand model S40A-300 pneumatic tool, which has moderate speed, stable operation, and reliable quality, and can meet the relevant technical requirements of pneumatic motors for conventional oil pipe (Ф73×5.51mm) rotary cup inner wall coating equipment. Performance parameters: working air pressure: 0.63MPa, no-load speed: 18000r / min, no-load air consumption: 10L / s, external dimensions: 300×Ф37mm, machine weight: 1kg. The selected pneumatic grinding wheel motor has a long service life and high reliability. A rotary cup support transmission shaft 2 is fixedly installed at the output end of the pneumatic motor 1, and a rotary cup 3 is fixedly installed at the front end of the rotary cup support transmission shaft 2. The rotary cup 3 has a paint cavity 4 inside, and the side wall of the suspension cup 3 corresponds to the paint. The cavity 4 has three vertical paint mist outlets 5 around its circumference. The specifications of the vertical paint mist outlets 5 are (2.0-4.0)×(15-23)mm. They are used to generate paint mist through high-speed rotation of the rotary cup and centrifugal ejection. The pneumatic motor 1 has a paint delivery pipe 6 that matches its outer contour. The front end of the paint delivery pipe 6 is inserted into the paint cavity 4 of the rotary cup 3. The paint cavity 4 is open. Multiple fixing seats 7 are fixedly connected to the outer wall of the paint delivery pipe 6. The fixing seats 7 are welded and fixed to the housing of the pneumatic motor 1. The tail end of the paint delivery pipe 6 is fixedly connected to a paint pipe connector 8. The tail end of the pneumatic motor 1 is fixedly connected to an air pipe connector 9. The rotary cup 3 is covered with a dispersion net 10. With the participation of the external dispersion net, the high-speed rotating rotary cup 310 can make the paint layer inside the rotary cup 3 centrifugally ejected to the vertical paint mist outlets 5, resulting in a finer and more uniform atomization of the paint particles. The paint film sprayed onto the inner wall of the oil pipe is continuous, fine, and uniform.

[0024] The rotating cup support drive shaft 2 includes a connecting part 11, a clamping part 12, an extension part 13, and a threaded part 14. The connecting part 11, clamping part 12, extension part 13, and threaded part 14 are arranged sequentially. The length of the connecting part 11 is 24mm and the diameter is 6mm. The length of the clamping part 12 is 9mm and the diameter is 8mm. The length of the extension part 13 is 37mm and the diameter is 6.85mm. The extension part 13 is relatively short, the distance between the rotating cup 3 and the pneumatic motor 1 is short, the rotating cup material is light, the vibration is small, and the stability is good. The length of the threaded part 14 is 19.5mm and the thread size is M5.

[0025] The connecting part 11 is used to connect with the pneumatic motor 1, and the threaded part 14 is used to connect with the rotary cup 3. The rotary cup 3 is threadedly connected to the threaded part 14. The connecting part 11 is inserted into the chuck of the pneumatic motor 1. The end of the threaded part 14 extends out of the rotary cup 3 and is threadedly connected to the nut 15. The rotary cup 3 has a rotary cup base fixing rod screw hole 17 for threaded connection of the threaded part 14 and through which it passes.

[0026] The rotary cup 3 is an inverted conical trapezoid, made of aluminum alloy. To prevent the coating from being atomized and spiraling out of the small cup opening when the rotary cup rotates, the cone angle is 5°-25°. The dispersing net 10 is an inverted conical trapezoid that is compatible with the rotary cup 3. Because the dispersing net 10 is an inverted conical trapezoid, during rotation, due to centrifugal force, the dispersing net 10 of the external rotary cup 3 is tightly fitted onto the rotary cup 3 and becomes tighter as it rotates, rather than detaching from the rotary cup 3 during rotation.

[0027] The screw hole 17 of the base fixing rod of the rotary cup is located at the large end of the rotary cup 3, and the paint cavity 4 is open to the small end of the rotary cup.

[0028] The distributed net 10 is fixedly installed to the rotary cup 3 by bolts, and the rotary cup 3 has threaded holes for bolt thread connection.

[0029] The front end of the paint supply pipe 6 is sealed. Two paint outlet holes 16 are opened at 180° diagonally on the paint supply pipe 6. The specifications of the paint supply pipe 6 are Ф4.0×1.0mm, and the specifications of the paint outlet holes 16 are Ф1.0mm. One of the paint outlet holes 16 is 4.5mm away from the top of the paint supply pipe 6, and the other paint outlet hole 16 is 9.5mm away from the top of the paint supply pipe 6. The paint outlet holes 16 of the paint supply pipe 6 are located in the middle of the longitudinal direction inside the rotary cup 3, which is conducive to the even longitudinal distribution of paint inside the rotary cup 3.

[0030] A method for applying a general-purpose rotary cup sprayer for curing coatings to the inner wall of oil pipes, comprising the following steps: Step 1: Preparation. Disperse the existing general-purpose curing coating using a dispersion device. The performance parameters of the original coating (the previously used commercially available curing coating) and the current coating (the currently used general-purpose curing coating) are compared in Table 1 below.

[0031] Table 1

[0032] The rotary cup spraying equipment for the inner wall of the oil pipe is connected to the front end of the nozzle transmission rod. The paint supply pipe 6 is connected to the paint supply machine through the paint pipe connector 8. The Ounac brand QPT2251K pneumatic paint supply machine is used, and the air source requirements are 0.6Mpa and 1m. 3 / min, pressure ratio is 22:1, pneumatic motor 1 is connected to air compressor through air pipe connector 9; Step Two: Spraying. High-speed rotary cup 3 high-pressure airless spraying is driven by pneumatic motor 1. The rotary cup 3 rotates at high speed under the drive of pneumatic motor 1. The paint is transported to the paint chamber 4 of the rotary cup 3 through the paint delivery pipe 6. In the high-speed rotating rotary cup 3, the paint adheres to the inner cup surface due to centrifugal force and is atomized at the vertical paint mist outlet 5 under the action of centrifugal force. The atomized paint is then passed through the dispersion net 10 by the centrifugal force of the rotary cup 3 and adheres to the inner wall of the oil pipe to form a continuous and uniform coating film. During the spraying process, the rotary cup spraying equipment on the inner wall of the oil pipe sprays the surface of the inner wall by moving backward along the axis parallel to the axis of the oil pipe. The rotary cup 3 is placed in the center of the oil pipe and moves backward to spray paint. The spraying of the rotary cup 3 is delayed by the pneumatic rotation, and the start and end points of the spraying can be precisely controlled.

[0033] The self-designed aluminum alloy conical trapezoidal rotary cup features three vertically positioned windows at 120° angles to each other, resulting in excellent atomization. A dispersion mesh covers the rotary cup, promoting even atomization and distribution. Two outlets, at 180° angles and staggered, are located in the middle of the rotary cup, ensuring relatively uniform paint supply. A pneumatic grinding wheel motor is used, offering long lifespan and high reliability. The rotary cup, positioned in the center of the oil pipe, moves backward during spraying, with the spraying delay compared to the pneumatic rotation, allowing for precise control of the spraying point. The short distance between the rotary cup and the pneumatic motor, combined with the lightweight material, minimizes vibration and enhances stability. The system boasts high paint utilization, low pollution, high efficiency, and high occupational health and safety.

[0034] This equipment achieves excellent surface quality and a continuous, uniform coating. It boasts high paint utilization, with a paint transfer efficiency exceeding 85% (paint transfer efficiency refers to the ratio of the actual amount of paint sprayed onto the target surface to the total amount of paint in the spraying equipment). Paint loss is minimal, as no air is involved in atomization, resulting in low paint dispersion and minimal loss. It improves work efficiency; when the paint viscosity is ≤12000 mPa·s, a 100-300 μm film can be obtained per application. Environmentally friendly and energy-saving, it is suitable for high-solids, high-viscosity coatings, reducing solvent usage. Furthermore, the new green heavy-duty anti-corrosion coatings use environmentally friendly solvents with even lower usage. The operating environment exhibits extremely low volatile organic compound (VOC) emissions, improving occupational health and safety management levels.

[0035] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A general-purpose rotary cup spraying equipment for the inner wall of a curing coating oil pipe, comprising a pneumatic motor (1) connected to the front end of the nozzle transmission rod, characterized in that: The output end of the pneumatic motor (1) is fixedly installed with a rotary cup support drive shaft (2), and the front end of the rotary cup support drive shaft (2) is fixedly installed with a rotary cup (3). The rotary cup (3) is provided with a paint cavity (4). The side wall of the suspended cup (3) is provided with three vertical paint mist outlets (5) corresponding to the circumference of the paint cavity (4). The pneumatic motor (1) is provided with a paint delivery pipe (6) that matches its outer contour. The front end of the paint delivery pipe (6) is inserted into the paint cavity (4) of the rotary cup (3). The paint cavity (4) is open. The outer wall of the paint delivery pipe (6) is fixedly connected with multiple fixed seats (7). The fixed seats (7) are welded and fixed to the outer shell of the pneumatic motor (1). The tail end of the paint delivery pipe (6) is fixedly connected with a paint pipe connector (8). The tail end of the pneumatic motor (1) is fixedly connected with an air pipe connector (9). The outer cover of the rotary cup (3) is provided with a dispersion net (10).

2. The universal curing coating oil pipe inner wall rotary cup spraying equipment according to claim 1, characterized in that: The rotating cup support drive shaft (2) includes a connecting part (11), a clamping part (12), an extension part (13), and a threaded part (14). The connecting part (11), clamping part (12), extension part (13), and threaded part (14) are arranged in sequence. The length of the connecting part (11) is 24 mm and the diameter is 6 mm. The length of the clamping part (12) is 9 mm and the diameter is 8 mm. The length of the extension part (13) is 37 mm and the diameter is 6.85 mm. The length of the threaded part (14) is 19.5 mm and the thread size is M5.

3. The universal curing coating oil pipe inner wall rotary cup spraying equipment according to claim 2, characterized in that: The connecting part (11) is used to connect with the pneumatic motor (1), the threaded part (14) is used to connect with the rotary cup (3), the rotary cup (3) is threadedly connected to the threaded part (14), the connecting part (11) is inserted into the chuck of the pneumatic motor (1), the end of the threaded part (14) extends out of the rotary cup (3) and is threadedly connected with a nut (15), and the rotary cup (3) is provided with a rotary cup base fixing rod screw hole (17) for threaded connection of the threaded part (14) and through which it passes.

4. The universal curing coating oil pipe inner wall rotary cup spraying equipment according to claim 1, characterized in that: The rotating cup (3) is in the shape of an inverted cone trapezoid, and the dispersing net (10) is in the shape of an inverted cone trapezoid that is adapted to the rotating cup (3).

5. The universal curing coating oil pipe inner wall rotary cup spraying equipment according to claim 3, characterized in that: The screw hole (17) of the base of the rotary cup is located at the large end of the rotary cup (3), and the paint cavity (4) is open to the small end of the rotary cup.

6. The universal curing coating oil pipe inner wall rotary cup spraying equipment according to claim 1, characterized in that: The dispersing net (10) is fixedly installed to the rotating cup (3) by bolts, and the rotating cup (3) has a threaded hole for bolt thread connection.

7. The universal curing coating oil pipe inner wall rotary cup spraying equipment according to claim 1, characterized in that: The front end of the paint supply pipe (6) is sealed. Two paint outlet holes (16) are opened at 180° diagonally on the paint supply pipe (6). The specifications of the paint supply pipe (6) are Ф4.0×1.0mm, and the specifications of the paint outlet holes (16) are Ф1.0mm. One of the paint outlet holes (16) is 4.5mm away from the top of the paint supply pipe (6), and the other paint outlet hole (16) is 9.5mm away from the top of the paint supply pipe (6).

8. A spraying method for a general-purpose rotary cup spraying equipment for curing coatings on the inner wall of oil pipes, characterized in that: The method steps are as follows: Step 1: Preparation. Disperse the existing general-purpose curing coating through a dispersion device. Connect the rotary cup spraying equipment on the inner wall of the oil pipe to the front end of the nozzle transmission rod. Connect the paint supply pipe (6) to the paint supply machine through the paint pipe connector (8). Connect the pneumatic motor (1) to the air compressor through the air pipe connector (9). Step 2: Spraying, high-speed rotary cup (3) high-pressure airless spraying, driven by pneumatic motor (1), the rotary cup (3) rotates at high speed under the drive of the pneumatic motor (1), the paint is transported to the paint chamber (4) of the rotary cup (3) through the paint delivery pipe (6), and the paint adheres to the inner cup surface by centrifugal force in the high-speed rotating rotary cup (3), and is atomized at the vertical paint mist outlet (5) under the action of centrifugal force. The atomized paint is passed through the dispersion net (10) by the centrifugal force of the rotary cup (3) and adheres to the inner wall of the oil pipe to form a continuous and uniform coating film. During the spraying process, the rotary cup spraying equipment on the inner wall of the oil pipe sprays the surface of the inner wall by walking backward along the axis parallel to the axis of the oil pipe.

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